<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        .container {
            width: 300px;
            height: 300px;
            border: 1px solid #ccc;
            display: flex;
            flex-flow: column wrap;
        }
        .container div {
            width: 80px;
            height: 80px;
            text-align: center;
            line-height: 80px;
            font-size: 24px;
            font-weight: bold;
        }
        .container div:first-child {
            margin-left: 0;
            margin-top: 0;
            background: chartreuse;
        }
        .container div:nth-child(2) {
            margin: auto;
            background: chocolate;
        }
        .container div:last-child {
            margin-left: auto;
            margin-bottom: 0;
            background: darkblue;
        }

    </style>
</head>
<body>
    <div class="container">
        <div>1</div>
        <div>2</div>
        <div>3</div>
    </div>
</body>
</html>